| Line 42... |
Line 42... |
use neorv32.neorv32_package.all;
|
use neorv32.neorv32_package.all;
|
|
|
entity neorv32_cpu_bus is
|
entity neorv32_cpu_bus is
|
generic (
|
generic (
|
CPU_EXTENSION_RISCV_C : boolean := true; -- implement compressed extension?
|
CPU_EXTENSION_RISCV_C : boolean := true; -- implement compressed extension?
|
BUS_TIMEOUT : natural := 15; -- cycles after which a valid bus access will timeout
|
|
-- Physical memory protection (PMP) --
|
-- Physical memory protection (PMP) --
|
PMP_USE : boolean := false; -- implement physical memory protection?
|
PMP_USE : boolean := false; -- implement physical memory protection?
|
PMP_NUM_REGIONS : natural := 4; -- number of regions (1..4)
|
PMP_NUM_REGIONS : natural := 4; -- number of regions (1..4)
|
PMP_GRANULARITY : natural := 16 -- granularity (1=8B, 2=16B, 3=32B, ...)
|
PMP_GRANULARITY : natural := 16 -- granularity (1=8B, 2=16B, 3=32B, ...)
|
);
|
);
|
| Line 133... |
Line 132... |
type bus_arbiter_t is record
|
type bus_arbiter_t is record
|
rd_req : std_ulogic; -- read access in progress
|
rd_req : std_ulogic; -- read access in progress
|
wr_req : std_ulogic; -- write access in progress
|
wr_req : std_ulogic; -- write access in progress
|
err_align : std_ulogic; -- alignment error
|
err_align : std_ulogic; -- alignment error
|
err_bus : std_ulogic; -- bus access error
|
err_bus : std_ulogic; -- bus access error
|
timeout : std_ulogic_vector(index_size_f(BUS_TIMEOUT)-1 downto 0);
|
timeout : std_ulogic_vector(index_size_f(bus_timeout_c)-1 downto 0);
|
end record;
|
end record;
|
signal i_arbiter, d_arbiter : bus_arbiter_t;
|
signal i_arbiter, d_arbiter : bus_arbiter_t;
|
|
|
-- physical memory protection --
|
-- physical memory protection --
|
type pmp_addr34_t is array (0 to PMP_NUM_REGIONS-1) of std_ulogic_vector(data_width_c+1 downto 0);
|
type pmp_addr34_t is array (0 to PMP_NUM_REGIONS-1) of std_ulogic_vector(data_width_c+1 downto 0);
|
| Line 312... |
Line 311... |
-- instruction fetch request --
|
-- instruction fetch request --
|
if (i_arbiter.rd_req = '0') then -- idle
|
if (i_arbiter.rd_req = '0') then -- idle
|
i_arbiter.rd_req <= ctrl_i(ctrl_bus_if_c);
|
i_arbiter.rd_req <= ctrl_i(ctrl_bus_if_c);
|
i_arbiter.err_align <= i_misaligned;
|
i_arbiter.err_align <= i_misaligned;
|
i_arbiter.err_bus <= '0';
|
i_arbiter.err_bus <= '0';
|
i_arbiter.timeout <= std_ulogic_vector(to_unsigned(BUS_TIMEOUT, index_size_f(BUS_TIMEOUT)));
|
i_arbiter.timeout <= std_ulogic_vector(to_unsigned(bus_timeout_c, index_size_f(bus_timeout_c)));
|
else -- in progress
|
else -- in progress
|
i_arbiter.timeout <= std_ulogic_vector(unsigned(i_arbiter.timeout) - 1);
|
i_arbiter.timeout <= std_ulogic_vector(unsigned(i_arbiter.timeout) - 1);
|
i_arbiter.err_align <= (i_arbiter.err_align or i_misaligned) and (not ctrl_i(ctrl_bus_ierr_ack_c));
|
i_arbiter.err_align <= (i_arbiter.err_align or i_misaligned) and (not ctrl_i(ctrl_bus_ierr_ack_c));
|
i_arbiter.err_bus <= (i_arbiter.err_bus or (not or_all_f(i_arbiter.timeout)) or i_bus_err_i) and (not ctrl_i(ctrl_bus_ierr_ack_c));
|
i_arbiter.err_bus <= (i_arbiter.err_bus or (not or_all_f(i_arbiter.timeout)) or i_bus_err_i) and (not ctrl_i(ctrl_bus_ierr_ack_c));
|
--if (i_arbiter.err_align = '1') or (i_arbiter.err_bus = '1') then -- any error?
|
--if (i_arbiter.err_align = '1') or (i_arbiter.err_bus = '1') then -- any error?
|
| Line 366... |
Line 365... |
if (d_arbiter.wr_req = '0') and (d_arbiter.rd_req = '0') then -- idle
|
if (d_arbiter.wr_req = '0') and (d_arbiter.rd_req = '0') then -- idle
|
d_arbiter.wr_req <= ctrl_i(ctrl_bus_wr_c);
|
d_arbiter.wr_req <= ctrl_i(ctrl_bus_wr_c);
|
d_arbiter.rd_req <= ctrl_i(ctrl_bus_rd_c);
|
d_arbiter.rd_req <= ctrl_i(ctrl_bus_rd_c);
|
d_arbiter.err_align <= d_misaligned;
|
d_arbiter.err_align <= d_misaligned;
|
d_arbiter.err_bus <= '0';
|
d_arbiter.err_bus <= '0';
|
d_arbiter.timeout <= std_ulogic_vector(to_unsigned(BUS_TIMEOUT, index_size_f(BUS_TIMEOUT)));
|
d_arbiter.timeout <= std_ulogic_vector(to_unsigned(bus_timeout_c, index_size_f(bus_timeout_c)));
|
else -- in progress
|
else -- in progress
|
d_arbiter.timeout <= std_ulogic_vector(unsigned(d_arbiter.timeout) - 1);
|
d_arbiter.timeout <= std_ulogic_vector(unsigned(d_arbiter.timeout) - 1);
|
d_arbiter.err_align <= (d_arbiter.err_align or d_misaligned) and (not ctrl_i(ctrl_bus_derr_ack_c));
|
d_arbiter.err_align <= (d_arbiter.err_align or d_misaligned) and (not ctrl_i(ctrl_bus_derr_ack_c));
|
d_arbiter.err_bus <= (d_arbiter.err_bus or (not or_all_f(d_arbiter.timeout)) or d_bus_err_i) and (not ctrl_i(ctrl_bus_derr_ack_c));
|
d_arbiter.err_bus <= (d_arbiter.err_bus or (not or_all_f(d_arbiter.timeout)) or d_bus_err_i) and (not ctrl_i(ctrl_bus_derr_ack_c));
|
--if (d_arbiter.err_align = '1') or (d_arbiter.err_bus = '1') then -- any error?
|
--if (d_arbiter.err_align = '1') or (d_arbiter.err_bus = '1') then -- any error?
|
